export function watermark(settings) {
    clear();
    // 默认设置
    const defaultSettings = {
        watermark_txt: settings.watermark_txt,
        watermark_x: 20, // 水印起始位置x轴坐标
        watermark_y: 20, // 水印起始位置Y轴坐标
        watermark_rows: 20, // 水印行数
        watermark_cols: 20, // 水印列数
        watermark_x_space: 100, // 水印x轴间隔
        watermark_y_space: 50, // 水印y轴间隔
        watermark_color: '#EEE9E9', // 水印字体颜色
        watermark_alpha: 0.4, // 水印透明度
        watermark_fontsize: '10px', // 水印字体大小
        watermark_font: '微软雅黑', // 水印字体
        watermark_width: 210, // 水印宽度
        watermark_height: 80, // 水印长度
        watermark_angle: 20 // 水印倾斜度数
    }
    /* if (arguments.length === 1 && typeof arguments[0] === 'object') {
        var src = arguments[0] || {}
        for (key in src) {
            if (src[key] && defaultSettings[key] && src[key] === defaultSettings[key]) continue
            else if (src[key]) defaultSettings[key] = src[key]
        }
    }*/
    var oTemp = document.createDocumentFragment()
    // 获取页面最大宽度
    var page_width = Math.max(document.body.scrollWidth, document.body.clientWidth)
    var cutWidth = page_width * 0.0150
    var page_width = page_width - cutWidth
    // 获取页面最大高度
    var page_height = Math.max(document.body.scrollHeight, document.body.clientHeight) - 35
    page_height = Math.max(page_height, window.innerHeight - 35)
    // 如果将水印列数设置为0，或水印列数设置过大，超过页面最大宽度，则重新计算水印列数和水印x轴间隔
    if (defaultSettings.watermark_cols === 0 || (parseInt(defaultSettings.watermark_x + defaultSettings.watermark_width * defaultSettings.watermark_cols + defaultSettings.watermark_x_space * (defaultSettings.watermark_cols - 1)) > page_width)) {
        defaultSettings.watermark_cols = parseInt((page_width - defaultSettings.watermark_x + defaultSettings.watermark_x_space) / (defaultSettings.watermark_width + defaultSettings.watermark_x_space))
        defaultSettings.watermark_x_space = parseInt((page_width - defaultSettings.watermark_x - defaultSettings.watermark_width * defaultSettings.watermark_cols) / (defaultSettings.watermark_cols - 1))
    }
    // 如果将水印行数设置为0，或水印行数设置过大，超过页面最大长度，则重新计算水印行数和水印y轴间隔
    if (defaultSettings.watermark_rows === 0 || (parseInt(defaultSettings.watermark_y + defaultSettings.watermark_height * defaultSettings.watermark_rows + defaultSettings.watermark_y_space * (defaultSettings.watermark_rows - 1)) > page_height)) {
        defaultSettings.watermark_rows = parseInt((defaultSettings.watermark_y_space + page_height - defaultSettings.watermark_y) / (defaultSettings.watermark_height + defaultSettings.watermark_y_space))
        defaultSettings.watermark_y_space = parseInt(((page_height - defaultSettings.watermark_y) - defaultSettings.watermark_height * defaultSettings.watermark_rows) / (defaultSettings.watermark_rows - 1))
    }
    var x
    var y
    for (var i = 0; i < defaultSettings.watermark_rows; i++) {
        y = defaultSettings.watermark_y + (defaultSettings.watermark_y_space + defaultSettings.watermark_height) * i
        for (var j = 0; j < defaultSettings.watermark_cols; j++) {
            x = defaultSettings.watermark_x + (defaultSettings.watermark_width + defaultSettings.watermark_x_space) * j
            var mask_div = document.createElement('div')
            mask_div.id = 'mask_div' + i + j
            mask_div.className = 'mask_div'
            mask_div.appendChild(document.createTextNode(defaultSettings.watermark_txt))
            // 设置水印div倾斜显示
            mask_div.style.webkitTransform = 'rotate(-' + defaultSettings.watermark_angle + 'deg)'
            mask_div.style.MozTransform = 'rotate(-' + defaultSettings.watermark_angle + 'deg)'
            mask_div.style.msTransform = 'rotate(-' + defaultSettings.watermark_angle + 'deg)'
            mask_div.style.OTransform = 'rotate(-' + defaultSettings.watermark_angle + 'deg)'
            mask_div.style.transform = 'rotate(-' + defaultSettings.watermark_angle + 'deg)'
            mask_div.style.visibility = ''
            mask_div.style.position = 'absolute'
            mask_div.style.left = x + 'px'
            mask_div.style.top = y + 'px'
            mask_div.style.overflow = 'hidden'
            mask_div.style.zIndex = '9999'
            // 让水印不遮挡页面的点击事件
            mask_div.style.pointerEvents = 'none'
            mask_div.style.opacity = defaultSettings.watermark_alpha
            mask_div.style.fontSize = defaultSettings.watermark_fontsize
            mask_div.style.fontFamily = defaultSettings.watermark_font
            mask_div.style.color = defaultSettings.watermark_color
            mask_div.style.textAlign = 'center'
            mask_div.style.width = defaultSettings.watermark_width + 'px'
            mask_div.style.height = defaultSettings.watermark_height + 'px'
            mask_div.style.display = 'block'
            oTemp.appendChild(mask_div)
        }
    }
    document.body.appendChild(oTemp)
}

export function getNow() {
    var d = new Date()
    var year = d.getFullYear()
    var month = change(d.getMonth() + 1)
    var day = change(d.getDate())
    var hour = change(d.getHours())
    var minute = change(d.getMinutes())
    var second = change(d.getSeconds())

    function change(t) {
        if (t < 10) {
            return '0' + t
        } else {
            return t
        }
    }
    var time = year + '年' + month + '月' + day + '日 ' + hour + '时' + minute + '分' + second + '秒'
    return time
}

function clear() {
    document.querySelectorAll(".mask_div").forEach(v => v.remove());
}
